Contacts:

Barbara Sullivan Sullivan& Associates (714) 374-6174 bsullivan@sullivanpr.com

Christina Andrian diaDexus, Inc. (650) 246-6476 candrian@diadexus.com

DIADEXUS TO PRESENT AT JPMORGAN'S 25TH ANNUAL HEALTHCARE CONFERENCE

South San Francisco, CA - January 2, 2007 - Patrick Plewman, president and chief executive officer of diaDexus, Inc., will present a corporate overview and an update on the commercial opportunity for the PLAC® test at the JPMorgan 25th Annual Healthcare Conference in San Francisco Monday, Jan. 8, 2007. The presentation will be held at the Westin St. Francis Hotel and will begin at 8 a.m. PST.

The conference is the largest in the healthcare industry and includes presentations by medical, scientific, and investment experts representing approximately 300 public and private companies. Institutional investors, portfolio managers, venture capitalists, company executives, scientists, and other industry leaders will attend the conference.

About diaDexus
diaDexus, Inc., a privately held biotechnology company based in South San Francisco, is focused on the discovery, development, and commercialization of innovative, patent-protected diagnostic products with high clinical value. The company’s lead product, the PLAC test, is a simple blood test that measures the concentration of a novel risk factor for coronary heart disease and stroke—lipoprotein-associated phospholipase A2 (Lp-PLA2), a cardiovascular-specific inflammatory marker implicated in the formation of vulnerable, rupture-prone plaque. The PLAC test is cleared for marketing by the U.S. Food and Drug Administration as an aid in determining risk for coronary heart disease and ischemic stroke associated with atherosclerosis. In addition to the PLAC test, diaDexus is developing a pipeline of novel cancer diagnostic tests.

For more information, visit www.plactest.com or www.diaDexus.com.